Isolated Splenic Metastasis from Non-Small-Cell Lung Cancer: A Case Report and Review of the Literature

Abstract

Metastases to the spleen are rare but have been reported for different tumor entities, including breast cancer, lung cancer, colorectal cancer, ovarian cancer, and melanoma. As an isolated event, splenic metastasis from non-small-cell lung cancer (NSCLC) is exceedingly rare. Until now, only 28 cases have been reported in the medical literature. We report the case of a 66-year-old woman with NSCLC (adenocarcinoma) who presented with a synchronous, isolated splenic metastasis. Operative removal of both primary tumor and metastasis was not possible due to multiple comorbidities. Therefore, treatment was limited to combined systemic chemotherapy and simultaneous radiation of the primary tumor, which led to partial remission of the disease. Isolated metastasis to the spleen in NSCLC has been reported only 28 times in the medical literature, most often in male patients with right-sided lung tumors, most of which were adenocarcinomas. The majority of patients were asymptomatic with respect to splenic metastasis. About half of the reported cases were isolated metachronous splenic metastases. Splenectomy seems to confer a survival advantage. We review the pertinent medical literature.

Solitary Splenic Metastasis of Lung Cancer Presenting as Benign Cystic Disease

“…1,2) Solitary splenic metastasis is extremely rare and only 31 cases have been reported previously. [3][4][5] The spleen is relatively resistant to metastatic seeding. Immune cells that play a role in immune surveillance are present in high density in the spleen, help to eliminate the cancer cells before they proliferate, and because of high concentration of antiangiogenic factors, the spleen creates an environment that is not advantageous to the growth of metastatic cancer cells.…”

“…Immune cells that play a role in immune surveillance are present in high density in the spleen, help to eliminate the cancer cells before they proliferate, and because of high concentration of antiangiogenic factors, the spleen creates an environment that is not advantageous to the growth of metastatic cancer cells. 3,6,7) Some reports have described the usefulness of FDG-PET for detection of splenic metastasis. 8,9) In the present case, however, FDG uptake was not observed in the splenic tumor.…”

Stereotactic Body Radiation Therapy to a Splenic Metastasis in Oligoprogressive Non-small Cell Lung Cancer

“…Splenic metastasis is often treated definitively by splenectomy in the setting of an isolated metastasis or oligometastatic disease. 6,33,34 To our knowledge, only 4 cases of SBRT to splenic metastases have been reported in the medical literature, with 2 cases describing a partial and complete response, respectively. [35][36][37] In the present case, SBRT of the splenic mass resulted in pseudoprogression at 1-month post-SBRT, followed by partial and complete response within 4 and 10 months, respectively.…”

“…4 NSCLC most commonly metastasizes to the brain, bone, lung, adrenal gland, and liver. Splenic involvement occurs in only 1%-6% of lung cancer 5,6 and is usually part of an extensive metastatic process. 6,7 Although stereotactic body radiation therapy (SBRT) is frequently used to treat a limited number of metastases (up to 5) in oligometastatic NSCLC, the role of aggressive metastasisdirected treatment in diffuse metastatic disease is not well established.…”

“…Splenic involvement occurs in only 1%-6% of lung cancer 5,6 and is usually part of an extensive metastatic process. 6,7 Although stereotactic body radiation therapy (SBRT) is frequently used to treat a limited number of metastases (up to 5) in oligometastatic NSCLC, the role of aggressive metastasisdirected treatment in diffuse metastatic disease is not well established. 8,9 The case presented here describes a progressive splenic metastasis from NSCLC treated with SBRT to achieve a durable complete tumor response in the setting of widespread, but otherwise stable systemic disease while on immunotherapy with nivolumab.…”